Composition of asphalt saturants



Patented 13, .1942

UNITED STATES. PATENT oFFicE '3 z,z1o,o4r- COMPOSITION OF SATUBANTSHenry S. Goodwin, East Bound Brook, and Herman I). Winters, Jr., RosellePark,

ors to Standard 011 Development Company, a corporation of Delaware NoDrawing. Application December 30, 1939, Serial No. 311,932

down.

particularly asphalt saturants that are used to waterproofasbestos-cement or similar types of building boards.

Building boards composed of asbestos fiber and Portland cement whencombined under pressure into a homogeneous dense mass have high strengthand great durability. Building boards being exposed to damp or wetweather for any substantial periods of time, there is a tendency of theboards to absorb sufflcient moisture to 1 cause the board .to'swell orcreep. Therefore,

substantial openings are required at the joints new edges of the boardare exposed when cutting. or breaking the board into smaller-pieces.

According to the present invention, it has been found that improvedsaturation of the boards with bitumen may be achieved at roomtemperatures and normal pressures by the application of asphalt incutback form. The percentage of asphalt in the cutback determines thepenetration of the saturant in the building boards .com-

of this type may be made in different forms for posed of asbestos fiberand Portland cement, that various purposes, that is, they may be made inis, when a saturant containing inthe neighborflat sheets and used asside walls, both indoor hood of 35 to 40% of asphalt dissolved in asoland outdoor. They may be corrugated and used vent naphtha having agravity varying from 28 as roofing and sidings. There is one disadvanto48 A. P. I., a kauri butanol solvent power tage in using boards of thistype, that is, upon varying from 53 to 82 and boiling points between 168F. and 450 F. is used according to this invention, an optimumpenetration is obtained. The following table is used to illustrate thedepth to which the saturant penetrates in asbestoscement boards:

Effect of composition of saturant on its penetrating ability towardasbestos-cement boards Physical inspection of Penetration of boardComposition of saturant mt mm depth Asphalt Solvent used saybflt Percent used Per cent (boiling Gravity Flash g gf g After After Afterasphalt (melting solvent range A. P. I. at 140 OF 2 hrs. 4 hrs; 6 hrs.

pt.). 237432 F. m8

F. F. 140 80 Naphtha 26. 0 90 82 2% 2% 40 140 0.- 17. 4 90 86 3 4 4 60140 40 o.-..... 9. 3 90 129 1 2 2% 20 135 so 30.1 150 so 2% 2% 3 35 185n 22. 9 150 102 3 3 4 65 185 35 r 8. 5 150+ 869 M M M 20 185 .0. 26. 183 3 3 3 35 185 65 19. 4 90 87 3 3% 4 40 185 60 16.9 90 92 2 4 4 60 18540 9. 3 90 183 3 3 65 185 35 7. 5 203 1 1 1 is that when fastening theboards in place pro- 45 vision must be made to allow for such creepingor swelling of the board.

An object of this invention is to impregnate these boards to such asubstantial depth with a waterproofing composition that substantially no50 moisture will be absorbed.

Another object of this invention is to impreghate these boards to such asubstantial depth with a waterproofing composition that substantially nomoisture will be absorbed even though 55 According to this table,cutbacks containing smaller or greater proportions of the asphalts ofvarious melting points do not penetrate to the same degree, that is, thegreatest penetration has been obtained when a cutback' asphalt containsapproximately 35 to 40% of the desired asphalt that is used in thepreparation of the cutback. It is desirable to use solvents having finalboiling points not over 400 or 450 F. Othersolvents may be used, forexample, hydrocarbon liquids having a boiling point below 400 F.,halogenatedhyd-rocarbons havingboiling points below 400 F., carbondisulfide, carbon tetrachloride,

chlorofornumethylene chlorideand the'lower boiling mono-chlor aliphatichydrocarbons, together with pyridine, nitro-benzol, benzol aniline andmono-chlorbenzol.

Cutback asphalts having Saybolt universal viscosities varying from 85 to105 seconds are preferred. Solvents having boiling points below 425 F.are likewise preferred.

An improvement in the manufacture of an asbestos cement building boardwhich comprises impregnating an asbestos cement board with a. liquidsaturant having a Saybolt universal viscosity varying'from 85 to 105seconds at 140 R, an A. P. I. gravity of 16.9 to 22.9 and consisting of35 to 40% or an asphalt having a melting point of 140 to 185 F. and 65to 60% of a solvent naphtha having an A.-P. Iigravity of 28 to 48 and akauri butanol solvent power of at least 53.

HENRY S. GOODWIN. HERE LAN D. WINTERS, JR.

